The present invention relates generally to x-ray lasers and, more particularly, to an ultrabright multikilovolt x-ray source which is based on the direct multiphoton excitation of hollow atoms from clusters using ultraviolet radiation, combined with a nonlinear mode of confined propagation or self-channeling.
Detailed molecular structural information is of enormous significance to the medical and biological communities. Since hydrated biologically active structures are small delicate complex three-dimensional (3D) entities, it is essential to have molecular scale spatial resolution, high contrast, distortionless, direct 3D modalities of visualization of specimens in the living state in order to faithfully reveal their full molecular architectures. An x-ray holographic microscope equipped with an x-ray laser as the illuminator would be uniquely capable of providing these images [1,2] and would have a peak brightness that is xcx9c105-fold higher than presently available synchrotron technology [3].
Accordingly, it is an object of the present invention to provide an apparatus and method for producing an ultrabright multikilovolt x-ray source.
Another object of the invention is to provide an apparatus and method for amplifying x-rays in the multikilovolt spectral region.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
To achieve the foregoing and other objects, and in accordance with the purposes of the present invention, as embodied and broadly described herein, the method for generating laser radiation in the x-ray region of the electromagnetic spectrum hereof includes: generating pulsed laser radiation having a chosen intensity and wavelength; generating gaseous atomic clusters having a chosen density and size; and directing the laser radiation into the gas clusters whereby multiphoton coupling with the clusters occurs producing rapid atomic excitation, thereby removing selected inner-shell atomic electrons without removing all of the electrons in the next outermost shell with the consequent generation of a population inversion, and whereby a nonlinear mode of confined propagation for x-radiation is produced.
In another aspect of the present invention in accordance with its objects and purposes, the apparatus for generating laser radiation in the x-ray region of the electromagnetic spectrum includes: means for generating pulsed laser radiation having a chosen intensity and wavelength; means for generating gaseous atomic clusters having a chosen density and size; and means for directing the laser radiation into the gas clusters whereby multiphoton coupling with the clusters occurs producing rapid atomic excitation, thereby removing selected inner-shell atomic electrons without removing all of the electrons in the next outermost shell with the consequent generation of a population inversion and the production of a nonlinear mode of confined propagation for x-radiation.
Benefits and advantages of the invention include the generation of multikilovolt x-radiation suitable for nanoscale imaging applications.